This proposal describes the feasibility stage of a multidisciplinary research project that will attempt to measure the efficacy of a culturally and developmentally appropriate school and family-based intervention to prevent obesity in American Indian children. Epidemiologic statistics and quasi-experimental control design will be used to assess the efficacy of primary prevention techniques applied to third, fourth, and fifth grade students from a cross section of schools on the Navajo reservation in New Mexico and Arizona. This project will be carefully designed to: l) produce educational materials and procedures that are culturally and geographically appropriate to this population, 2) pilot test all materials and procedures in this population, and 3) provide a model of program development and implementation applicable to other discrete populations. A school-based curriculum will be developed, implemented, and evaluated that focuses on promoting a healthful diet and increased physical activity. Methods used will be derived from social learning theory, developmental theory, sound educational practices, and by employing culturally relevant approaches to instruction. Native school staff, health educators, public health professionals and nutritionists will be a part of the team that plans, implements, and evaluates the curriculum. A special emphasis will be placed on the participation of families and communities in the project. For example, elders from the community will be invited into the classroom to share oral histories and to discuss the value of traditional foods (naturally low in fat and high in fiber) as well as sharing traditional approaches to being physically active and keeping life in balance. The project will draw upon and combine a variety of culturally, developmentally, and educationally appropriate primary prevention techniques. Approaches are based on previous Center for Indian Youth Program Development (CIYPD) research and prevention efforts that have been developed, implemented, and replicated in various American Indian communities and schools over the past 19 years. In the final analysis, this project will determine which aspects of primary prevention of obesity are most feasible with American Indian schoolchildren and their families. Additionally, valuable epidemiologic statistics on this discrete population will be collected.